For the most part in terms of SKU's Windows 7 has gone back to similar principles of windows xp at retail point. Windows 7 pro is for enthusiasts, IT pros, small business etc home premium is your defacto necessary for home and common usage. starter and enterprise have separate purposes and will not be in retail channels besides OEM and hardware. Ultimate is really unnecessary one which really similar to vista has combined package of really enterprise and professional in one.
I'll personally probably be going the Technet subscription path soon with discount to get it along with everything else